Hydraulic power transmission apparatus



Sept. 19, 1939. P. M. SALERNI HYDRAULIC POWER TRANSMISSION APPARATUS Filed Oct. 5, 1935 12M w/mq; W M

Patented Sept. 19, 1939 UNITED STATES.

HYDRAULIC POWER TRANSMISSION APPARATUS Piero Mariano Salerni, England, assignor to Salerni, Nice, France Application October Westminster, London, Marie Therese Elisabeth 5, 1935, Serial No. 43,789

In Great Britain June 16, 1933 11 Claims.

This invention relates to hydraulic power transmission apparatus and has reference to hydraulic torque converting transmitters more especially for use in mechanically propelled vehicles. The type of transmitter to which the present invention relates is that in which power is transmitted by circulation of liquid within a closed circuit due to difierence in centrifugal head, as

for example in the Fottinger or similar type of transmitter.

According to the present invention I provide an impeller having vanes shaped or curved to deflect the liquid backwards relatively to the impeller the angle or curverequlsite to turn the liquid backwards relatively to the impeller beginning substantially at or extending substantially from the major radius of the circuit.

Further, according to this invention the delivery ends of the vanes are turned backwards relatively to the impeller or the direction of primary motion from a point in or near to the said major radius in such manner as to deflect the liquid backwards by a substantial angle relatively to the direction in which the liquid approaches the said point. By substantial angle I mean an angle of at least 20 but not so large as to cause the rate of revolution of the impeller to become so high, when transmitting power under the conditions for which the apparatus is designed, as to introduce losses which neutralize the increase of efliciency obtained by the said backwards deflection. The delivery ends of the impeller vanes are preferably arranged to extend beyond the point at which the circuit attains its major radius. The efiect of the arrangement according to the invention is to increase the emciency of the transmitter. The turbine vanes may be substantially straight and radially disposed.

In order that the invention may be clearly understood and readily carried into eifect, the same will now be more fully described with reference to the embodiment shown in the accompanying drawing, in which:

Figure 1 illustrates a sectional view of the circuit of one type of hydraulic power transmitter comprising an impeller, a turbine and a reaction or tertiary member and embodying the present invention.

Figure 2 is a diagrammatic developed view showing an impeller vane and a turbine vane according to the invention.

In the example illustrated, the impeller is indicated by the reference letter A, having vanes A the impeller being mounted on or connected with the driving shaft in any appropriate manner. The reference letter B indicates generally the turbine which is secured to the driven shaft in any appropriate manner, the vanes of the turbine being indicated by B C indicates a tertiary or reaction member having vanes Q which,

when operative, function to deflect in the direction of primary motion the liquid issuing from the turbine. The said tertiary member may be of any appropriate type or form. With regard to the construction illustrated in Figure l, the operation is generally as set forth. in the specification of my patent application Ser. No. 730,161 flied June 11, 1934, so that further description with regard to the general operation and construction of the transmitterv is present application is in part a continuation of my aforesaid application Serial No. 730,161. It is to be understood, however, that the present invention can be applied to other constructions. The present invention is concerned with the formation of the is shown more particularly in Figure 2 which illustrates a preferred form of the invention diagrammatically. The impeller vane, which as aforesaid is indicated by the reference letter A is, as shown, straight or radially disposed from its receiving end A towards the major radius, whence it is curved or shaped so as to terminate in a deflecting portion A which is directed back- Wards relatively to the direction of primary motion by approximately which is a backwards angle that has been found to be adequate in certain cases, but it will be understood that the backwards angle can be Varied according to requirements, so long as the angle is such as to deflect the liquid near the impeller outlet by a substantial angle relatively to the direction in which the liquid approaches the major radius of the circuit. In the example illustrated, the impeller portion of the circuit attains its major radius, at some distance from the delivery ends of the impeller vanes, for instance, as indicated at A the vanes being turned backwards from this point to their delivery and so that a substantial change in the direction in which the liquid flows through the impeller is efiected near the impeller outlet. In this specification and in the claims the expression "major radius of the circuit means that part of the circuit the outer boundary of which lies outside an imaginary cylinder of infinite length whose axis is the axis of rotation and which is just large enough in diameter to contain the inner boundary of the circuit.

In the example shown in Figure 1, X, X is a section of the wall of the said imaginary cylinder, which intersects the outer boundary of the circuit at Y, Y. The major radius of the circuit is the part of the circuit whose outer boundary is Y, y, Y', i. e. the part between the lines Y, Z, Y, Z' more remote from the axis of rotation, which lines are the shortest that can be drawn from the point Y, Y on the outer boundary to the inner boundary. I have found that the arrangement according to this invention enhances the not necessary. The

impeller vanes, and this formation eiiiciency of the apparatus; One of theadvantages' of the present invention is thatit renders it practicable to avoid the use of turbine vanes of which the receiving ends are turned or curvedbackwards relatively to the direction of primary preferably arranged to be substantially straight and radially disposed as shown.

What I claim and desire to secure by Patent of the United States is:

1. A hydraulic power transmitter. wherein power is transmitted by circulation of liquid within a closed circuit due to difference in centrifugal head of the type wherein the torque imparted by hydraulic means to the turbine can be substantially greater than that imparted to the impeller and which comprises an impeller having its outlet in the major radius of the circuit and delivering liquid having a component of velocity in the axial direction, a vaned turbine and a vaned reaction member, the vanes of the impeller forming ducts which near its outlet are turned backwardly relatively tothe direction of its angular motion from a point in or near to the said major radius by a substantial angle relatively to the direction in which the liquid approaches the said point. whereby the liquid is caused to leave the impeller with a component of velocity in the direction of its angular motion smaller than that with which the liquid approaches the said point.

2. A hydraulic power transmitter wherein power is transmitted by circulation of liquid within a closed circuit due to difierence in centrifugal head of the type wherein the torque imparted by hydraulic means to the turbine can be substantially greater than that imparted to the impeller and which comprises a vaned impeller having its outlet in the major radius of the circuit and delivering liquid having a component of velocity in the axial direction, a vaned turbine and a vaned reaction member, the impeller extending throughout a substantial portion of the major radius of the circuit and having vanes forming ducts which near its outlet are turned backwardly relatively to the direction of its angular motion Iroma point in or near the major radius by a substantial angle relatively to the direction in which the liquid approaches said point, whereby the liquid is causedto leave the impeller with a component of velocity in the direction of its angular motion smaller than that with which the liquid approaches the said point;

3. A hydraulic power transmitter wherein power is transmitted by circulation of liquid within a closed circuit due to diilerencein centrii'ugal head of the type wherein the torque imparted by hydraulic means to the turbine can be substantially greater than that imparted to the impeller and which comprises a vaned impeller having its outlet in the major radius of the circuit and delivering liquid having a component of velocity in the axial direction, a vaned turbine and a vaned reaction member, the im-,

peller extending throughout a substantial portion of the major radius of the circuit and having vanes forming ducts which are turned backwardly relatively to the direction of its angular motion from a point at the beginning of the major radius of the circuit towards the outlet of the impeller by a substantial angle relatively to the direction in which the liquid approaches the said point, whereby the liquid is caused to leave the impeller with a component 01 velocity in the Letters within a closed circuit due to difference in centrifugal head of the type wherein the torque imparted by hydraulic meansto theturbin'e can be substantially greaterjthan that imparted to'the impeller and-which comprisesavaned impeller having its outlet in the major radius oi the circuit and delivering liquid having a component of velocity in the axial direction, a vanedturbine and avaned reaction member, the impeller having vanes forming ducts which near its outlet are turned backwardly relatively to the direction of its angular motion from a point in or near the major radius by a substantial angle relatively to the direction in which the liquid approaches the said point, whereby the liquid is caused to impinge upon and to be deflected by the backwardly curvedparts of the vanes near their delivery ends and to leave the impeller with a component of velocity in the direction of its angular motion smaller than that with which the liquid approaches the said point.

5. A hydraulic power transmitter wherein power is transmitted by circulation of liquid within a closed circuit due to difference in centrifugal head of the type wherein the torque imparted by hydraulic means to the turbine can be substantially greater than that imparted to the impeller and which comprises a vaned impeller having its outlet in the major radius of the circuit and delivering liquid having a component of velocity in the axial direction, a vaned turbine and a vaned reaction member, the impeller having its vanes disposed substantially radially from, or from near its inlet up to a point in or near to the major radius oithe circuit and from the said point to or towards its outlet, having the ducts formed between its vanes turned backwardly relatively to the direction of its angular motion by a substantial angle relatively to the direction in which the liquid approaches the said point, whereby the liquid ,iscaused to leave the impeller with a component of velocity in the direction of its angular motion smaller than that with which the liquid approaches the said point.

7 direction [of its angular motion sifri'aller than that with whichthe liquld' .approachesjthe said point. '4.,A '-hydraulic power transmitter wherein power is'transmitted by circulation of liquid 6. A hydraulic power transmitter as in claim 5, in which the vanes of the impeller are substantially radially disposed from the inlet end to a point at or near the major radius of the circuit and are then turned backwards.

'7. A hydraulic power transmitter as in claim 1, comprising an impeller with vanes the backwardly turned portions whereof decrease in thickness gradually towards the delivery ends.

.8. A hydraulic power transmitter as in claim 2, comprising an impeller with vanes the backwardly turned portions whereof decrease in thickness gradually towards the delivery ends.

9. A hydraulic power transmitter as in claim 3, comprising an impeller with vanes the backwardly turned portions whereof decrease in thick-' ness gradually towards the delivery ends.

10. A hydraulic power transmitter as in claim 4, comprising an impeller with'vanes the backwardly turned portions whereof decrease in thickness gradually towards the delivery ends.

11. A hydraulic power transmitter as in claim 5, comprising an impeller with vanes the back- 'wardly turned portions whereof decrease in thickness gradually towards the delivery ends.

PIERO MARIANO SALERNI. 

